Re: Priority implementation complexity (was: Re: Extensible Priorities and Reprioritization)

Dmitri Tikhonov <> Tue, 09 June 2020 14:47 UTC

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Date: Tue, 9 Jun 2020 10:44:29 -0400
From: Dmitri Tikhonov <>
To: Lucas Pardue <>
Cc: HTTP Working Group <>, Bence =?iso-8859-1?Q?B=E9ky?= <>, Kazuho Oku <>
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Subject: Re: Priority implementation complexity (was: Re: Extensible Priorities and Reprioritization)
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On Tue, Jun 09, 2020 at 03:15:44PM +0100, Lucas Pardue wrote:
> I can hypothesize that an implementation with QPACK dynamic support has
> already crossed the threshold of complexity that means implementing
> reprioritization is not burdensome. I'd like to hear from other
> implementers if they agree or disagree with this.

I don't think we can judge either way.  If Alice implements QPACK and
Bob implement reprioritization, results will vary based on their level
of competence.  The degree of burden will also vary for each
particular implementation.  Speaking for lsquic, reprioritization
had to [1] touch more code and was much more tightly coupled than
QPACK; on the other had, QPACK encoder logic was a lot more code.

At a higher level, I don't understand the concern with complexity.
If you look up "complexity" in the dictionary, you will see

    complexity (n), see QUIC.

  - Dmitri.

1. Before it was ripped out of the spec, that is, thanks a lot...